The Oncology Nursing Society's (ONS's) mission is to promote excellence in oncology nursing and quality cancer care. In order to accomplish this mission, new knowledge is needed in areas where there are gaps relevant to oncology nursing practice. This document is written to support a proposed State-of-the-Science conference on Sleep Disturbances in People with Cancer and Their Caregivers. The conference will serve as the first step in synthesizing existing knowledge and generating new knowledge that will chart the direction for nurse scientists to take in order to reduce the distress associated with sleep disturbances, particularly insomnia, in adults and children with cancer and their caregivers. Insomnia is defined as difficulty falling asleep, staying asleep and/or frequent nighttime awakenings with daytime consequences in physical, psychological and social dimensions. Efforts to identify the nature, prevalence, assessment and treatment of insomnia in people with cancer and in their caregivers have been almost invisible to date in comparison to the work that has been done in the areas of pain, anxiety/depression and fatigue. It is time to clarify the role insomnia plays, both alone and as part of symptom clusters, in the symptom experience of people with cancer. Specific aims of the conference related to people with cancer and caregivers include: 1) Determine the state of the science related to sleep and sleep disturbances, particularly insomnia; 2) Begin development of research and clinical guidelines for measuring sleep and insomnia; 3) Identify evidence-based pharmacological and non-pharmacological interventions for insomnia; and 4) Prioritize areas for future research and education in related to insomnia and related symptoms and clusters. Outcomes of the proposed conference will include a manuscript outlining the state of the science related to sleep disturbances/insomnia in adults and children and a blueprint/plan for future research; both will be widely disseminated to researchers, clinicians and educators in oncology and to members of multi-disciplinary organizations whose focus in on sleep and sleep disturbances, particularly insomnia.